Many Indian IT business process outsourcing (BPO) providers have managed to sustain operations, amid the massive power cuts that has hit over 20 states including the capital New Delhi.

According to the Economic Times (ET) on Tuesday, three power grids in the country failed, starting with the northern grid which collapsed for the second day in a row, followed by the eastern and north-eastern grids. The three grids carry about 50,000 MW of electricity, it noted.

This has led the BPO industry, which accounts for 7 percent of the country's gross domestic product (GDP) to fall back on back-up generators that run on diesel, said ET.

WNS Group CEO Keshav R Murugesh, told the Times of India: "The building infrastructure has dual back up support of gas and diesel. The critical and non-critical resources were put on optimum utilization to control the wastage."

He added that his company which houses about 5,000 employees at a delivery centre in Gurgaon in the state of Haryana--one of areas hit--did not suffer any business loss.

Another player Genpact also reported business as usual. "There is no impact at any of the Genpact sites due to the power failure. We have a back-up plan in place and have a four-day supply of diesel," the company's senior vice-president for infrastructure and logistics, Vidya Srinivasan told news agency PTI.

The northern grid, which caters to power supply in at least nine states collapsed at 2.35am on Sunday night, according to the Times of India.

The news daily noted that essential services and public transport systems such as railways have also been hit, which have caused some problems for companies in terms of traffic delays affecting staff.

"The major shifts affected were the early morning shifts. To support and sustain the operations, we also had back up of transport at various stations," Murugesh said.

Loves caption contests, leisurely strolls along supermarket aisles and watching How It's Made. Ryan has covered finance, politics, tech and sports for TV, radio and print. He is also co-author of best seller "Profit from the Panic". Ryan is an editor at ZDNet's Asia/Singapore office.